The Integrated Homestead: Soil Care Practices

“The Integrated Homestead”

Soil nurture has to become as important to us as the nurture of our children.

Adding Organic Matter

Again, I cannot stress too strongly that soil fertility is not something we buy in a bag. Our main soil fertility strategy should be encouraging maximum diversity and population densities of soil-dwelling organisms, and “feeding” the soil with the maximum amount and variety of organic matter possible. If you are eager to feed your soil with any and all organic materials you can get your hands on, you will cringe hearing reference to organic “wastes.” Nothing that our soil-dwelling friends consider a veritable feast should ever be thought of as waste. Remember that the organic residues from numerous projects on the homestead—deciduous leaves, grass clippings, spent crop plants, weeds—can become food energy for the soil food web and, eventually, humus. Hauling such treasures to the landfill is a crime against sustainability.

Neighbors who may not have the same perspective on the “black gold” in their back yards may be eager to part with them—their loss can be your gain. I have a neighbor who hauls oak leaves to me by the pickup load. I bow down to her and say “Thank you! Thank you!”

Mulches

Certainly the easiest way to use available organic residues is mulching. Try to think where in nature you ever see bare soil. Either soil is covered with a dense profusion of plants, or with a natural mulch like fallen leaves or, in winter, the dead foliage of perennials awaiting the time to emerge for another round next spring. Anywhere your own garden or orchard is not covered with plants, cover it with similar organic residues. Practically speaking, this means that any clean-up chore like raking leaves, mowing the lawn, weeding, pruning, or wood chipping (your own or someone else’s) is an opportunity to protect the soil and boost its fertility with mulches.

Mulches protect the moisture and texture of the soil, while moderating temperature extremes—all ideal conditions for encouraging proliferation of soil organisms, who then “eat” the mulch even faster and convert it to humus. Some mulches are appropriate in garden beds, tucked in between crop plants, such as straw, leaves, or grasses cut from pasture. Others are not appropriate there, such as prunings or wood chips or sawdust, but can be well used in pathways or around the base of trees.

Remember cardboard and newsprint as high-carbon mulching materials. American and European cardboard is safe to use in such applications (cardboard from elsewhere may or may not be), as is all newsprint these days (with the possible exception of slick, highly colored parts of the newspaper, which I discard). Cardboard and newspaper, covered by other materials like wood chips or grass clippings to hold them in place, make great plant-suppressing cover over garden or orchard paths, or “kill mulches” for smothering an established sod.

Even quite coarse materials like prunings from orchard trees can be used in mulches. When I prune my fruit trees, I put the prunings down as the bottom layer of a mulch that is not going to be disturbed for a long time. For example, I use them to line the paths through the forest garden, cover them with cardboard or newspaper, then put on a finish cover of wood chips, stable bedding, grass clippings, etc. Or I might use them as the first layer of a “kill mulch” in the forest garden, in preparation for establishment of a permanent ground cover.

Manures

Nothing that comes out of the far end of a domesticated animal should be overlooked as a source of soil fertility! Whether you bring in manures from neighbors who see them as more nuisance than treasure, or whether you are seeking responsible management of manure from your own livestock, make this “black gold” a source of fertility rather than environmental pollution or vector for disease. Sometimes it is appropriate to work fresh manures into the soil. For example, the nutrients in manures (particularly their nitrogen content) are available for immediate uptake by heavy feeding crops like corn and squash. However, fresh manures can cause problems for germination of some crop seeds. Also, excessive use of manures—especially in clay soils—can lead to unhealthy buildup of salts. It is usually better to use manures in the making of composts (or to do something really fun like vermicomposting).

The question of humanure

More enlightened agriculturalists in this country strive to utilize animal manures for their fertility, while preventing their serving as a vector for disease or source of water contamination. But there is one animal whose manure is almost universally ignored as a source of recaptured fertility: Homo sapiens. We prefer the sleight of hand of the flush toilet to whisk our own eliminations “out of sight, out of mind.” This temporary convenience has devastating consequences, however, whether these potential nutrients are flushed away thoughtlessly into natural water systems (where they act more like environmental toxins than beneficial nutrients); or whether they are processed into “sludge” or (the preferred euphemism these days) “biosolids,” which are applied to agricultural lands despite carrying a heavy load of heavy metal and other industrial contaminants, with toxic effects that will last generations.

Ultimately we have to make more sane and sustainable use of the substances our own bodies eliminate as no longer usable (but which are a major potential nutrient source for the soil food web). I don’t have much hope there will be an outbreak of sanity at the governmental/regulatory level anytime soon. Even at the homestead level, in most jurisdictions, doing something more sensible with our own poops is likely to be a criminal act. I’ll just close by noting that a proof-of-concept humanure composting operation (involving little more than a couple of plastic buckets and a composting bin) can be very low-profile indeed. Joe Jenkins’s The Humanure Handbook is the bible for homesteaders interested in experimenting.

Compost

Clasically the ideal way to convert organic materials to soil fertility is the making of composts. Assemble the heap with layers of more nitrogenous components such as fresh green material (fresh cut pasture grasses, green crop plant residues like pea vines), hay, or manures—alternating with layers of higher carbon materials such as straw and leaves. Make sure the mix is loose enough to provide oxygen for decompositional microbes, and is neither sopping wet nor dry. With the right mix of carbon and nitrogen (at an ideal ratio of about 30:1), air, and water, the decompositional microbes utilize the nitrogen in the mix as energy as they break down the carbonaceous materials to simpler components usable by plant roots as nutrients. Properly made compost also carries a huge load of beneficial microorganisms that boost the microbial populations in the soil.

In the decomposition process, the microbes generate a good deal of heat. Some gardeners like an extremely hot compost heat, to kill disease organisms and weed seeds, and to hasten the breakdown process. Others believe that a hotter compost heap destroys potential nutrients, or volatilizes them to the atmosphere (especially nitrogen, in the form of ammonia). This is an area for research of your own. My own tendency is again to conclude that patience is a virtue; and that a compost that takes longer to finish retains more nutrients and makes a greater contribution to soil carbon.

Sheet composting

Composters may debate technique, but all agree that making compost in classic heaps is labor intensive. As I get older, I prefer lazier alternatives. One is “sheet composting,” “layer composting”—some even call it “lasagna gardening.” Rather than assembling compost heaps (which have to be laboriously turned two or three times during the breakdown process), we lay over a garden bed the greener, more moist, and nitrogenous materials we would use in a compost heap—and cover them with the drier, coarser, more carbonaceous materials as a protective cover. The soil microbes, earthworms, and other transformation artists feed on the more readily used bottom layer, while being protected from drying and temperature extremes by the coarser layer above. Eventually, of course, just as in a standard mulch, all the material is broken down and drawn into and through the soil food web.

Such a sheet-composted bed can be left for a season for the process to complete. There is no reason we shouldn’t crop that bed, however. It is possible to open holes in the layers and plant large transplants such as tomatoes, peppers, broccoli, and cabbages. We can open up a furrow just wide enough to sow rows of beans in the bed. If we’re generous with the water during germination, we can even broadcast a crop like cowpeas into the top layer, rake the seeds in just enough to cover them, and keep them moist enough to germinate and start to grow. From that point, the sheet compost will benefit the plants, and the close cover will speed up its decomposition by soil dwellers.

Vermicomposting

Converting organic residues to fertility using earthworms is fun—maybe a rewarding project for the younger members of the family—and can be done at any scale. You can buy ready-made worm composting bins, but I started with a simple frame of 2×10 lumber, three feet by four feet, dug into the soil inside my greenhouse. For bedding, I used coir (particulate residue from the processing of coconut husks for fiber), though other organic materials can be used, including shredded cardboard. For four years I cycled all the kitchen refuse that we didn’t feed to the chickens—vegetable peelings, banana peels, coffee grounds, tea leaves—through the bin as feed for the worms. (Technically, these vegetable residues serve as food for teeming bacteria, who are fed on in turn by the worms.) When one section of the bin had been converted to pure castings (earthworm poop), I removed them for application in the garden. As with compost from a compost heap, worm castings contain not only nutrients easy for plant roots to assimilate, but large numbers of microbes to boost the soil microbial populations.

Though many “vermiculturists” use self-contained bins, I simply dug my 3 by 4-foot frame into clay soil. There is no reason to be concerned that the worms will escape from the bin: Earthworms used in vermicomposting are the “red wriggler” or “manure worm” type (Eisenia foetida is the species most often used) that you would find in an aged manure heap, not the “night crawler” types that burrow deep into the soil. The composting worms will not burrow into the packed clay under a worm bin, nor will they crawl out the top. The nutrient-rich bedding prepared for them is just where composting worms want to be, and they will stay in the bin, eating the bounty provided and reproducing prolifically, rather than leaving the bin for a less hospitable environment outside.

Cover crops

What a great idea for soil fertility—grow your own! The gardener should miss no opportunity to grow cover crops, in every bed not required for current cropping, in every season of the year, in every nook and cranny. When cover crops are killed, their green biomass is fed upon by bacteria and other members of the soil food web. Their roots decay (are consumed by microbes) in place, loosening the soil well into its deeper layers and opening it to penetration by air and rain. Grain cover crops, especially rye, have extensive root systems and thus add a lot of biomass to the soil, and eventually humus. Cover crops in the legume family (beans and peas, clovers, alfalfa, and many others) set nitrogen in the soil, for a big boost in fertility. It’s a great idea to precede heavy feeding crops like corn and garlic with a legume cover. Buckwheat does not add as much biomass to the soil, but it is amazingly fast-growing (from seed to flower in thirty days in my garden), and is a good choice for getting in a quick cover between a spring and a fall crop. Oats also come up fast and offers a tight cover, so is often used—like buckwheat—as a “nurse crop” for more permanent plantings like alfalfa, covering the plot closely enough to keep the soil cool and moist, and discouraging competition from weeds. When these more short-lived nurse crops die or are mowed, the permanent crop comes on strong.

Please seize every opportunity to grow cover crops, which can serve so many functions at once. Cover crops do double duty as sources of cut material for mulches and composting, and fodder for livestock. Increasing the diversity of plants on your homestead by growing cover crops also increases the diversity of key animal species like earthworms and insects. You can undersow a cover like Dutch white, a low-growing clover, into beds with a small “footprint” such as pole beans or trellised tomatoes.

Winter is too often neglected as an opportunity to grow cover crops, though protection of the soil over winter is perhaps more crucial than at any other point in the year. I sow every bed to cover crop just as soon as the late summer or fall crop is off. In late summer I have more options (cowpeas, clovers, crucifers, all the small grains). By fall, my best option might be rye or vetch (or a mix), which will germinate and establish later into the chilly season than any other crop.

Perhaps you’ll be more motivated to plant winter covers if you remember a strategy I love: growing a heavy mulch right in place. In the asparagus beds, for example, it’s great to mulch to prevent weed growth, keep the asparagus spears clean, conserve soil moisture, and add to organic matter. But I don’t purchase expensive mulches, or move my mulches from distant parts of my pasture. Instead, I cut the asparagus fronds in late September, and sow the beds to a mix of oats and field peas (Pisum arvense, a close relative of the garden pea). These fast-growing crops grow thick and lush, knee-high, through the frosts of fall and early winter (the peas setting nitrogen for the heavy-feeding asparagus). When the ground freezes solid, however, these two plants reliably winter-kill in my climate (Zone 6b), lying down into the most beautiful mulch for the spring season you can imagine.

Fertility patches

Certain plants are especially useful in fertility patches, grown specifically for use in fertility applications. Comfrey and stinging nettle are excellent examples. Both are high in protein (nitrogen), and can be used to “fire” a compost heap, or for mulches. (I applied heavy nettle/comfrey mulches on my potato beds last year, and harvested the biggest spuds ever.) Both will benefit from massive infusions of organic fertility, in any form you can throw at them, even raw poultry manure. I am planting comfrey and nettle along one entire boundary of our property, which is not needed for other crops, and taking frequent cuttings of them to boost fertility elsewhere.

If at all possible, we should try to have at least as much ground growing “fertility crops” as food crops, preferably more. If that sounds like a lot, remember that any pasture ground you have can be a fertility patch par excellence: Especially when growth is fast and lush in the spring, you should be able to take a cutting, perhaps two, for use in composting or as mulches. If you do not have any pasture, consider using parts of your lawn instead, perhaps those less visible if you are nervous about a neighborhood outcry. I have begun overseeding my lawns each fall with the same sort of grass/clover mix I use on the pasture. In the spring, I allow some areas to grow about eight or ten inches before cutting with the scythe for fertility applications.

Protecting Soil Structure

Avoid excessive tillage

There are of course times when massive disruption of garden soil is necessary, as when digging potatoes or sweet potatoes. With these exceptions, however, we should avoid tillage as much as possible. Tillage breaks down the “crumb structure” built up by many soil-life processes, and inverts the natural layers of the soil profile. It is also erosive.

We usually think of soil erosion as the washing away of soil by rain, or of the blowing away of dry, exposed soil in the wind (both of which destructive effects are increased in soil that has been tilled). But there is a third, critical type of erosion: the oxidization of the carbon component (humus) through excessive exposure to oxygen. Oxygen is essential to soil life, but the required amounts are supplied by the opening up of the soil by earthworms, decayed plant roots, and soil aggregation. Frequent deep tillage exposes humus in soil to excess oxygen, which combines with it to form carbon dioxide. Yes, that carbon dioxide—CO₂, the greenhouse gas. Though we think of greenhouse gas accumulation primarily as exhausts from our countless infernal combustion engines, actually modern agricultural practices emit enormous amounts of CO₂ to the atmosphere as well.

That’s the bad news. The good news is that we start to reverse atmospheric carbon dioxide accumulation as we change our agricultural practices. It has been estimated that every 1 percent increase of carbon in a garden’s soil is equivalent to the weight of all the carbon in the atmosphere above that garden, right out to the vacuum of space. By reducing tillage while adding all the organic matter we can, we reverse CO₂ emission: Carbon is sequestered (bound up) in soil in the form of humus. The good news is that you can help ameliorate climate change in your own backyard.

The broadfork

Do note that there is one piece of shaped steel which can appropriately be used to loosen soil without breaking down its structure or inverting its layers. The broadfork consists of heavy 12- to 14-inch pointed steel tines, welded to a stout bar, to which is attached a pair of wooden or steel handles for leverage. The gardener kicks down or stands on the bar to push the tines full-length into the garden bed, pulls back on the handles to rock the tines in place and loosen the soil, and moves the broadfork over a few inches to repeat the process.

Please note that the broadfork is not appropriate for tilling tough sod to prepare new garden ground. (But note that a power tiller is not appropriate to this use, either. Anyone who has tried it will tell you: Attacking established sod over compacted soil with a power tiller will bust your butt!) It is better to start (slowly) either with a kill mulch over the sod, or by fencing a flock of chickens on the plot until they have killed the sod plants and turned them in. Either method can be followed by a cover crop; and by the time our hard-working friends in the soil have made some headway at “mellowing” the plot, we can start to use the broadfork to break it up further, allowing easier penetration by earthworm and root. It’s better to be satisfied initially with a penetration by the tines of only a few inches, rather than exhausting ourselves by heroically forcing them into the still-compacted depths of the soil.

As the soil in our no-till beds becomes more friable each year, it is possible to do whatever tillage is needed with ever greater ease. Eliot Coleman (author of The New Organic Grower, and an experienced market gardener) says: “I have used it [the broadfork] outdoors on areas up to one acre without feeling too much strain.” My own garden is fairly ambitious, at about 6000 square feet, and I have never regretted giving away, many years ago, the only power tiller I ever owned.

As the soil improves through our soil-feeding and no-till practices, it is less and less necessary to till even with the broadfork—it is increasingly possible simply to rake out the beds and plant.

Grow in wide beds

Grow garden crops in wide beds. Decide what is a comfortable reach for you, for planting and weeding—twice that distance should be the width of a bed you will work from opposite sides. My beds are 42 inches wide, with 18-inch paths between them. Keep all foot traffic in the pathways to avoid compaction of the beds. If it is necessary to stand on the bed for certain chores, stand on a piece of scrap plywood to spread your weight (and do this only when the soil is not wet).

Avoid bare soil

Bare soil is like a wound in the earth. Just as you cover a wound to protect it and hasten healing, so you should cover any soil bared in harvest or removal of cover crops, just as soon as possible. Applying mulches and growing undersown cover crops are great ways to cover the soil in a bed. It is also good practice to plant every crop as closely as it will permit—the merging canopy of leaves will protect soil moisture and moderate temperature extremes. Because it takes a while for the plant cover to establish in this way, an excellent strategy is to plant even more tightly. For example, plant four times the number of lettuce or broccoli raab transplants than the spacing in the literature suggests, and a protective canopy will establish in a fraction of the time. Then, as the plants start to crowd, give them more space by harvesting “baby greens.” You will have an earlier supply of green edibles, and will keep the bed covered for a greater part of the harvest cycle. Another strategy is to plant faster-growing crops (lettuces, radishes) between slower-growing ones (broccoli or cabbage, carrots, or beets). The faster crops are ready to harvest at about the time the slower ones are large enough to form a canopy over the bed.

Remineralizing the Soil

One of the great problems with current agricultural practice is the demineralizing of our soils, as revealed by the USDA’s own “composition of foods” analyses over the past decades, which show a trend toward ever less mineral (and other nutrient) content in our foods. This decline in mineral content should hardly be surprising in an agriculture that “feeds” the soil with soluble salts of only a few of the major elements needed by plants (mostly nitrogen, phosphorus, and potassium—and sometimes calcium), ignoring those that are essential even if required in smaller amounts—iron, sulfur, boron, magnesium, manganese, copper, selenium, etc.

One solution to the challenge of remineralizing our soil is the purchase of soil amendments. There is nothing wrong with this approach, subject to a couple of caveats. We should think of such amendments largely as a one-time thing, in order to make needed adjustments quickly. Not too quickly, however: Do not ever apply highly soluble amendments of any sort to your ground. Add slow-release rock powders and mined mineral deposits such as greensand, azomite, colloidal rock phosphate, and lime if soil tests suggest a need for amendment.

As for soil tests, use them with caution. Different laboratories use different testing reagents and techniques and apply different principles to interpretation. An experiment was done to test the soil testers: Identical samples were sent to one hundred different soil testing laboratories. The results varied widely, and made a bell curve when plotted on a graph.

It is best not to opt blindly for the testing service which is the cheapest or most convenient, but to seek out a soil consultant whose approach you have confidence in. You will pay more, but will likely get better information about your present soil condition and advice for amending it. For example, for years I used the free state soil testing service available through my county Extension Office. It always puzzled me that the results for phosphorus and potassium consistently reported as “very high”—and just as consistently, the advice was to use a fertilizer that contained 10 percent each of these elements. When I turned to a student of William Albrecht (one of our greatest soil scientists of the past century), he advised “no fertilizer needed” with regard to my oldest garden soil, and only lime and a little boron for my least-worked ground, my pasture.

But we must realize that in the long run, sustainability cannot mean transporting soil amendments to our back door from far away, at great energy expense. What are more local, more “integrative” solutions right on the homestead?

Fortunately, we’ve already begun on our remineralization strategy if we are maximizing the return of organic residues to the soil. These materials supply not only nitrogen for plant growth and carbon for humus formation, but as well the mineral components of the plant tissues or undigested nutrient matter (manures) involved. These mineral elements are made available in the trophic exchange pathways of the soil community, which boost their availability for uptake by plant roots.

Another strategy for increasing mineral content in our soil is the cultivation of dynamic accumulators in our fertility patches. Certain plants grow roots into the deep subsoil, and aggressively “mine” it for minerals that otherwise would not be available to more shallow-rooted plants. When these plants die or shed their foliage over winter, their mineral content is made available in the top layers of the soil profile. Dynamic accumulators include such useful plants as comfrey, stinging nettle, dandelion, and yellow dock. I am making extensive plantings of these plants—along borders, under fruit trees in the forest garden, and in any nook or cranny not dedicated to other uses.

A New Relationship with “Weeds”

“Wait a minute—‘useful plants like stinging nettle, dandelion, and yellow dock’? Those things are weeds! Are you nuts?”

It behooves us to get to know all the plants possible in our specific ecology, and to appreciate the role each plays, and the contributions it can make. (Yes, that includes poison ivy—that’s your koan for today.) With regard to the addition of organic matter via composts and mulches, weeds serve as well as any other organic material. But weeds tend as well to be aggressive scavengers of minerals in the soil and subsoil, with different weeds concentrating different mineral elements, and hence can be especially useful for remineralization.

It is far better for soil to be covered with weeds rather than bare. If there is a patch of soil that you will not be cropping for a while, and you don’t have the time to put it into cover crop, it might be a good idea to leave the weeds to establish as a natural cover crop. (I would advise, however, that you mow the patch occasionally in order to prevent a heavy set of seeds—those guys can get pushy if you don’t impose some limits.)

More and more, I am welcoming former “weeds” to take part in the ongoing festival that is our homestead. When dandelion and yellow dock volunteer in my forest garden, I either remove them or encourage them, depending on my needs for that space. If I encourage them, I can cut the foliage several times during the season to use in mulches, and allow these robust plants to regrow.